With the rapid development of the Internet, various types of data explosively emerge and grow. Because a blockchain features decentralization, tamper-resistance, distribution, etc., the blockchain technology is currently focused and studied in many technical fields.
In a blockchain application, both parties involved can offline agree on contract content or contract execution, and then store related data in a blockchain. In some blockchain applications, some transaction data in a blockchain can be viewed and analyzed by another node, for example, business activities of a member are analyzed based on the number of transactions submitted to the blockchain by the member within a time period, transaction types, and transaction participants. Apparently, the transaction data can be maliciously used in this way. Therefore, a solution that can more effectively ensure information security of transaction participants is urgently needed in a blockchain data service.